Dr. O'Donnell's basic and clinical research has a long history of focusing on bladder immunology and bladder cancer immunotherapy, particularly the anti-cancer mechanisms of bacillus Calmette-Gu�rin (BCG) and its enhancement with combination therapies. Dr. O'Donnell recently headed a national trial of bladder cancer treatment utilizing BCG plus interferon (a natural protein which induces healthy cells to combat disease) comprised of over 1,000 patients, and holds several U.S. patents for his work. While BCG has long been a standard treatment for bladder cancer, its toxicity profile can be devastating. Dr. O'Donnell's studies, both laboratory and clinical, seek to both determine the exact mechanism by which BCG targets bladder cancer tumor cells, and enhance its efficacy, either alone or in combination with other agents, while reducing its toxicity to healthy cells.